Good call.
Asimov wrote the original Foundation Trilogy in the 40s and 50s. When the publisher threw enough money at him, in the early '80s, he returned to the Foundation universe and published some of the most unreadable dreck to ever be vomited from the typewriter of an author who should know better. Each sequel to the original trilogy was progressively worse, undermining more and more of the original series as “modern” Asimov tried to refute “young” Asimov’s beliefs, ideas, concepts and technology.
When Asimov died, three new writers (Bear, Benford and Brin) made things even worse: rather than accept the original series, they proposes that robots had been beaming “stupid-rays” all over the galaxy to keep humans dumb (and to explain the relatively low tech).
Donald Kingsbury wrote an unauthorized “sequel” called Psychohistorical Crisis. It ignored all stories written after the last of Asimov’s original series and picked up as though none of the other stuff had been written. And it FAR outshines all the other sequels. It accepts and deals with the '50s techology, the '40s Kay Tarrant approved gender roles, etc.
It’s not an authorized sequel but the serial numbers have been filed off just barely enough to quiet the lawyers. The Mule becomes “The Cloun”, the Second Foundationers became “The Fellowship of Pscholars” and Terminus became “Faraway” but it’s the only sequel that keeps the culture and the ‘feel’ of the original series.
Also, I realize I’m in a minority of one, but I really liked Jack Snow’s two sequels to Baum’s Oz books. He’s the only one of the “official chronicler of Oz” who realized that there’s more to Oz than twee-cutesy places and (gasp) allowed conflict and challenges to occur (the two chroniclers post-Baum and pre-Snow were of the “Let’s have the characters wander around and see twee-cutesy places” variety). If the last 1/3d of Maguire’s Wicked was as good as the first 1/3d (or even the middle third), I’d include it as well.
**Aliens **as the sequel to **Alien **- again, not books, but as far as movies go, a great example of a different director doing great things with a sequel…
I have to third that.
It’s more of a prequel, and has a completely different tone, but Susan Kay’s Phantom has the best Erik outside of the original Phantom of the Opera. (I have a few quibbles, but…)
Another H. Beam Piper sequel was Roland Green’s Great Kings War, a sequel to Piper’s Lord Kalvan story. It was the first book I thought of when I saw the OP. I keep forgetting it’s not by the original author.
Victor Appleton, Jr’s Tom Swift, Jr. books were generally better than Victor Appleton’s Tom Swift books. 
Is this a joke or a woosh?
Color me confused as well.
The best of Goldsborough was about = to the worst of Stout, which made some of them readable. But not the later ones.
RealityChuck *How about Gregory Maguire’s Wizard of Oz sequels/prequels? * Not in the same world at all, just a few names are coincidental. Horrible as canon.
I read 1 and 1/2 of those. They stink like a day-old ass sandwich.
Do Androids Dream of Electric Sheep? wasn’t a favorite of mine; I basically just don’t like Dick. The sequels penned by KW Jeter, somehow, manage to be even worse.
Hm. I’ve got “The Dragon Lensman”. Now I gotta go hunt up the others…
One of the profoundly great works of Western Literature, Orlando Furioso by Ludovico Ariosto, is a direct sequel to one of the profoundly mediocre works of Western Literature, Orlando Inamorata by Matteo Boiardo.
Neither of them are novels, of course.
The bad press scared me off of John Betancourt’s sequels to Roger Zelanzy’s Amber series(es), so that likely belongs in the negative column.
If you want, I’ll send them to you. I have them on a shelf getting dusty.
I thought that Wide Sargasso Sea was a great complement to Jane Eyre. You may love or hate it, but Bertha’s story definitely needed telling and Rhys is a great writer.
Tom Holt wrote two sequels–Lucia in Wartime and Lucia Triumphant --after E.F. Benson died in 1941 shortly after writing his sixth Mapp and Lucia novel.
For those who don’t think that 6 books about Mapp and Lucia are enough (and they aren’t!), the two by Tom Holt are a satisfying addition.
Same here. The only thing that I like about Fuzzies and Other People (apart from the title) was that Gus got hisself some Fuzzies in that one. I hated the whole “teaching Fuzzies to lie” thing.
I’d be crazy to say no.
You wouldn’t by chance need any old Andre Norton books to round out your collection, would you? 
Oh, the first one was a horror! :eek: It reeked! Made Frank Herbert’s son look like a literary genius.